1. Field of the Invention
The present invention relates to a voice recognition apparatus and method for controlling equipment by recognizing the voice received from a user and more particularly to attempting to improve voice input operation.
2. Description of the Related Art
Use of electronic equipment using voice recognition for man-machine interface is on the increase in recent years. A car navigation is one example of the equipment. Such a car navigation functions as what is used to guide a vehicle from the present position up to a destination by designating a desired place to set the destination, searching for a route from the present position of the vehicle up to the destination and displaying the route together with a map on a display.
The designation of a place through voice operation in a car navigation is performed by voicing and inputting a message sequentially according to a guidance message, including the kinds of facilities such as schools, hospitals and stations existing in an intended place and finally designating a proper name in the place, for example, a facility name of “Meguro Station”.
However, due to the fact that the number of facilities tends to increase, a message of the facility name has been voiced after the intended number of facilities is narrowed down to a certain extent according to the area and category in order to specify the desired facility by means of voice recognition, which is intended to shorten response time, to improve the recognition ratio and to simplify the processing of the same name by narrowing down the intended number of facilities.
A facility retrieval procedure in a car navigation utilizing conventional voice recognition will now be described below.
At the initial stage, a control command dictionary for operating the car navigation is set on the system side. A user voices a command to “set a destination” whereby to transfer to the system an intention of setting a route up to a destination.
As the number of facilities is enormous though retrieving a specific place as a destination on the system side is needed, it is not practical to specify a place with voice recognition once because a reduction in the recognition ratio. In order to reduce the number of facilities as an object of retrieval, narrowing-down is performed on the category side. First, in order to have narrowing-down performed on a category basis, the system voices a guidance message of (1) “A category, please” after the recognition dictionary is replaced with the category name dictionary so as to urge the user to voice a message of the category name. In order to cope with this, when the user voices a message of (2) an “educational facility”, a voice recognition device recognizes the message.
As the system makes it a rule to have a detailed category designated as long as the education facility is concerned, a guidance message of (3) “Next category name, please” is outputted after the recognition dictionary is replaced with a sub-category name dictionary whereby to urge the user to voice the sub-category name. When the user voices a message of (4) “high school” therefor, the voice recognition device recognizes the message.
With the sub-category thus decided, the recognition dictionary is replaced with a prefectural name dictionary in order to perform narrowing-down in the area and then a guidance message of (5) “A prefectural name, please” is voiced to urge the user to narrow down the area with the municipality as a unit.
When the user voices (6) “the Metropolis of Tokyo”, the voice recognition device recognizes the message as “the Metropolis of Tokyo”. In case where the sub-category is “a high school” and the municipal name is “the Metropolis of Tokyo”, the system makes it a rule to have a municipal name designated. The recognition dictionary is replaced with a municipal name dictionary and then a guidance message of (7) “A municipal name, please” is outputted to urge the user to voice a municipal name. When the user voices (8) “Shibuya Ward”, the voice recognition device recognizes the message. As the number of facilities has sufficiently been narrowed down until then by the designations above, retrieval of the facility name is started.
The system then outputs a guidance message of (9) “Name, please” after replacing the recognition dictionary with a high school dictionary in Shibuya-ku to urge the used to voice a facility name. When the user voices “A ◯◯ educational institution”, the voice recognition device recognizes the message and sets the ◯◯ educational institution as a destination.
However, the narrowing-down of prefectures has been determined on the system side beforehand in the conventional system, it is needed to voice category and area names in the designated order when the category and area names are designated. Thus, the user is compelled to follow the procedure.